Posted on 02/23/2013 10:16:24 AM PST by SunkenCiv
Explanation: A meteoroid fell to Earth on February 15, streaking some 20 to 30 kilometers above the city of Chelyabinsk, Russia at 9:20am local time. Initially traveling at about 20 kilometers per second, its explosive deceleration after impact with the lower atmosphere created a flash brighter than the Sun. This picture of the brilliant bolide (and others of its persistent trail) was captured by photographer Marat Ametvaleev, surprised during his morning sunrise session creating panoramic images of the nearby frosty landscape. An estimated 500 kilotons of energy was released by the explosion of the 17 meter wide space rock with a mass of 7,000 to 10,000 tons. Actually expected to occur on average once every 100 years, the magnitude of the Chelyabinsk event is the largest known since the Tunguska impact in 1908.
(Excerpt) Read more at 129.164.179.22 ...
[Credit & Copyright: Marat Ahmetvaleev]
The object was about 55 feet across, blasted apart at 12 to 18 miles altitude, released approximately 500 megatons.
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The object was about 55 feet across, blasted apart at 12 to 18 miles altitude, released approximately 500 megatons.
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Kilotons, actually. I suspect that a 500-megaton airburst would wipe out a fairly large chunk of Russia.
I’m not buying this. WHERE are the pieces, and parts of an object that weighed so many tons! I think it was like a flat rock, that boys skip across ponds...and when it hit the atmosphere of the Earth, it skipped back into space! OR, there was some military experiment using high frequency SOUND WAVES to see how they could destroy a city instead of using explosives. This story doesn’t settle anything for me.
That is a neat picture! Thanks!
Most meteors are vapourized in the atmosphere, but if there is anything left one of two things can happen: Those with high metallic content will impact the surface of the earth, while rocky meteors tend to explode in the air. The amount of energy released is calculated from the mass and velocity of the object (E=MV^2/2).
Looks like something like that could really knock things up.
Shades of Robert Heinlein’s, The Moon is a Harsh Mistress. Just “throwing rocks” at cities could cause massive damage with none the radiation that nuclear weapons have.
I expect 500 kt would have been more than sufficient to wipe out Chelyabinsk, if the explosion had not occurred so high up (altitude estimated at 16 to 19 miles). I wonder what the SIOP had allocated to it, back in the day.
Before the shock wave arrived, the Russians had time to observe the flash, which lasted some seconds, building to a peak, and go outside with their cameras and pan back and forth at the sky, chattering excitedly. Then crack! Windows shattered, doors blown in, car alarms set off, dogs barking. Some 1100 people sought medical attention.
Looks like a great big sperm to me.
(i think i said that in post 8)
Why did the meteor explode?
Rocky meteors tend to explode in the air due to uneven heating; the leading surfaces are hotter and thermal expansion causes the rock to burst.
Same as most things, rapid heating and expansion of vapor from material heated far beond its vaporization temperature. Aerodynamic heating tends to be asymmetric with non-linear heat transfer, so it’s likely there was a massive outgassing that just blew the non-melted pieces apart from the central mass.
D’oh !
Same as most things, blah, blah, blah..teehee...
Friction.
Whoops. [blush]
The Russkies report three different impact sites from larger chunks; the damage to the town was from the shock wave, but small chunks of this will be found for some time, on the ground; much of the object just turned to (very hot) dust. And no, it didn’t skip back into space.
Manta.
From heaven.
Thanks, pally .................................................................................... FRegards
;’)
Kinetic energy.
Blah...blah...yuck...yuck...hee...haw...cluck...chuck...
Energy? What's that? How about... the conserved quantity associated with the temporal invariance of the Lagrangian density.
Yuk...yuk.
that is what they all say
I know. It’s all you can get out of these physics types sometimes.
They don’t call it Panspermia fer nuthin’ lol.
They don’t call it Panspermia fer nuthin’ lol.
I just looked up kinetic orbital bombardment on wiki, it’s wiki but I didn’t realize Pournelle came up with a proposal for it when he was at Boeing in the 50’s. I had heard of THOR but I didn’t realize it was that old. I knew he and Niven used it for Footfall, but that’s probably not news for you on account of your screen name.
http://en.wikipedia.org/wiki/Kinetic_bombardment
the ‘in science fiction’ section is pretty interesting.
Freegards
Actually, reports said the problem is that people ran to their windows to see what had happened. Then 3 minutes later about 4,000 buildings had their windows blown in. Three minutes at 5 seconds per mile = 36 miles away.
I have read elsewhere that people in London were able to read their newspapers at night from the light of Tungusku. I also read that a boloid strike in the Amazon, I think in the 1930s, flattened an area about 50 miles in diameter.
It has been reported elsewhere that hundreds of small chunks have been collected, and people are still looking. I would suspect that some of the larger ones would be hidden until the finder can figure how to get top dollar for it.
I can believe that, factoring in horizontal as well as vertical separation.
Actually, reports said the problem is that people ran to their windows to see what had happened. Then 3 minutes later about 4,000 buildings had their windows blown in.
I wonder how many of the injuries were caused by that reaction.
You can view a nice compilation of videos by Alexander Zaytsev. Outdoor Example. Indoor example. Another indoor example.
Separately, it's amazing the popularity of dash cams in Russia. It's apparently a defense against the prevalence of insurance fraud.
I have read elsewhere that people in London were able to read their newspapers at night from the light of Tungusku.
Not likely.
However, the Tunguska bolide, which arrived in 1908 about 1500 miles due east of Chelyabinsk, is estimated to have had a yield of 3 to 30 megatons. Also, it exploded at a much lower altitude and knocked down about 80 million trees. The few eyewitness accounts describe an event resembling a thermonuclear attack (minus the fallout, and other radiation effects, etc). If there had been a metropolis below, it would have been toast.
I also read that a boloid strike in the Amazon, I think in the 1930s, flattened an area about 50 miles in diameter.
The media are claiming the Chelyabinsk object is the biggest since Tunguska. For that reason, it would be neat if there really was a 'Brazilian Tunguska Event'. Of course, on the other hand, it would imply that such events are about twice as likely as commonly believed ...
That 36 mile estimate means it was some distance away, as well as 12 to 18 miles up. :’) The glow from Tunguska’s aftermath hung in the sky for some time, quite amazing consequences from a simple pile of space crud.
Thanks for bringing up the 1930s strike in the Amazon (or somewhere in the rain forest, perhaps the Orinoco Basin), the full extent of the damage is not known, probably was large, maybe not 50 miles.
There was also a strike in Greenland just in the past decade (or maybe a couple of decades, I’m behind in my email), and I’d posted recently about the Lake Michigan strike in the teens of the 20th century.
A Flash From the Past: New Evidence Supports Moon Blast · by Henry Fountain · March 4, 2003 -- On the Moon, material that is freshly exposed has a slight bluish tinge. Over time, because of the constant bomb ardment of cosmic rays, other high-energy particles and micrometeorites, the structure of the material changes and iron particles tend to predominate, making the material slightly red. In the Clementine photos, Dr. Buratti and Mr. Johnson found one small crater that was "very, very blue and fresh appearing," Dr. Buratti said. It also happened to be in the exact center of the area they were looking. And it was the proper size -- slightly less than a mile across, including the ejecta blanket. Dr. Bu ratti estimated the size of the asteroid at 20 yards in diameter.
A Celestial Collision · Alaska Science Forum · February 10, 1983 · Larry Gedney · Posted on 09/15/2004 9:04:28 AM PDT · by SunkenCiv -- Early in the evening of June 18, 1178, a group of men near Canterbury, England, stood admiring the sliver of a new moon hanging low in the west. In terms they later described to a monk who recorded their sighting, "Suddenly a flaming torch sprang from the moon, spewing fire, hot coals and sparks." In continuing their description of the event, they reported that "The moon writhed like a wounded snake and finally took on a blackish appearance"... [P]lanetary scientist Jack Hartung of the State University of New York... gathered enough clues to suggest that a large asteroid... might have smacked into the moon just over the horizon on the back side. To test his suspicion, Hartung went to the Lunar and Planetary Institute in Houston, and inspected Russian and American photographs of the moon's back side. Sure enough, in just the right place, he found a remarkably fresh crater, 12 miles across and twice as deep as the Grand Canyon. From it radiated white splatter marks for hundreds of miles... Such an impact, reason astrophysicists, would set the moon to ringing like a gong for thousands of years... At Texas' McDonald Observatory, astronomers Odile Calame and J. Derral Mulholland of the University of Texas find that the surface of the moon moves back and forth fully 80 feet! Such an oscillation clearly implies a collision with something large, sometime within the not-too-distant past, probably within the memory of mankind. The problem is that there is no way to peg the date exactly at 1178. ['Civ note: Larry Gedney died in 1992]
This event came as a surprise, as I've never heard it recounted by any of my elderly relatives, and most of them died before I read about it in this book. A number of other such impacts, including some which hit or nearly hit people, ships, animals etc, are described in this book, which I recommend. My review on Amazon is still there, but much shorter than I remember...Rain of Iron and Ice:On November 27,1919, a meteorite fell into Lake Michigan near the Michigan shore. "Residents of Battle Creek, Kalamazoo, South Bend, Grand Haven, and other Western Michigan cities fled from their homes in panic, fearing an earthquake. Houses were shaken, the country was illuminated as by a bright sun's rays, so all-enveloping it was impossible to tell from which direction the flare came, the earth trembled for half a moment and then came a deep prolonged rumbling as of a terrific explosion." (p 159)
The Very Real Threat of
Comet and Asteroid Bombardment
by John S. Lewis
Bolivian impact, Tunguska and other Russian impacts, and, uh, I forget... but related anyway...
http://www.freerepublic.com/focus/news/610489/posts?page=10#10
http://www.freerepublic.com/focus/news/747114/posts
http://www.freerepublic.com/focus/news/758204/posts
http://www.freerepublic.com/focus/news/765074/posts
http://www.freerepublic.com/focus/news/867877/posts
http://www.freerepublic.com/focus/news/925578/posts
http://www.freerepublic.com/focus/news/1025865/posts
http://www.freerepublic.com/focus/news/1152933/posts
http://www.freerepublic.com/focus/news/1619222/posts
http://www.freerepublic.com/focus/news/1809501/posts
http://www.freerepublic.com/focus/chat/1941279/posts
http://www.freerepublic.com/focus/news/1962278/posts
http://www.freerepublic.com/focus/news/1962278/posts?page=46#46
http://www.freerepublic.com/focus/news/2039577/posts
http://www.freerepublic.com/focus/chat/2558112/posts
http://www.freerepublic.com/focus/chat/2937621/posts
http://www.freerepublic.com/tag/impact/index
Now you’ve done it, made me go dig out my copy of “Impact Earth; Ateroids, Commets and Meteoroids, The Growing Threat”, by Austen Atkinson, 1999.;-) News reports said many of the injuries were from flying glass.
Impact Earth, pg. 22. “...[Tungusku] blast...at a height of approximately 8 km....burnt, defoliated and felled trees, and killed thousands of reindeer, across an area of approx. 2,000 sq. km.” “Games of cricket were played in London under an incandescent night sky that was said to be so bright as to allow a newspaper to be read at midnight.” Also an 18 time level of Iridium was found with the GISP2 Greenland ice core project.
IE, pg. 80. The Brazil event occurred in May 1931. An Amazon tribe was so shocked it was preparing mass suicide. A Catholic priest, who is apparently the source of this information, talked them out of it. It is suggested that this air burst was “equivalent to 4-8 Hiroshima sized atomic bombs.” It set afire 1,300 sq. kms. of rainforest. The square root of 1300 is about 36, so rounding out, it was probably an area 40 km. in diameter.
I wonder if Soddom and Gommorah was an air burst event?
This meteor was somewhat horizontal to the earth plane....I wonder what would have happened if it was vertical...would it have been able to make it to the ground?
This meteor was somewhat horizontal to the earth plane....I wonder what would have happened if it was vertical...would it have been able to make it to the ground?
This meteor was somewhat horizontal to the earth plane....I wonder what would have happened if it was vertical...would it have been able to make it to the ground?
That’s the one, 1931; didn’t know about the iridium layer for Tunguska, and it’s a nice detail, I’m going to grab your post text.
Sodom and Gomorrah was probably something besides impact, because in addition to the possible description of a fireball, the entire landscape was altered sometime between their disappearance (or rather, after the tribes departed for Egypt) and the return of the Hebrew tribes. The Jordan River formerly flowed in the Valley of Siddim (the OT explicitly states that what is now the Salt Sea was the Valley of Siddim in the time of Abraham), going north, then bent toward the Med, flowing down the Jezreel. It is now divided by a 600m ridgeline.
http://www.varchive.org/itb/overthrow.htm
http://www.varchive.org/itb/deadsea.htm
http://www.varchive.org/itb/rift.htm
Space begins at 100km altitude / 62 miles. Roughing it out, I’d say, maybe — a steeper course through the atmosphere might still lead to disintegration, but the transit through the atmosphere took mere seconds, so...
Thanks nti.
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